The winner depends on whether the SSD is mostly idle (Kingston SSD Now 128 GB), writing sequentially (Corsair F40) or writing randomly (Corsair Nova 128 GB). I expect that there are other alternatives as well, but I don't know of any complete listing for every drive on the market.

Most SSD power consumption reviews are completely wrong. Here's the deal: Some SSDs support DIPM, Device Initiated Power Management. This is not an automatic hardware feature, but something that has to be activated by a driver. Most SSD reviewers run automated test benches in either a scripted Linux Live CD (or usb stick) or some other means where they don't install drivers that are compatible with DIPM. This means that those drives that benefit from DIPM are usually not recognized. To add insult to injury, all reviewers without fail don't seem to be able to read the specs and see a huge discrepancy between the quoted power consumption figures and their measurements. Surely, if you see that the Postville Intel SSDs quote a power consumption of 75mW idle/150mW active and you are measuring 0.6W, something must be wrong?. No, they never investigate. Of course I have been an annoying user and wrote to most reviewers that made this error, but they either respond with 'nah, don't care' or 'can't change test bench, won't change reviews'. At the least, remove power consumption figures altogether if they're plainly wrong...

So, here's the low-down:- Intel-based 5x and 3xnm drives are the thriftiest, with 75mW idle power consumption and on average much less than their quoted 150mW. Peak consumption is somewhere in the 1-2W range.- Closely followed by 2xnm Intel drives that do 100mW/200mW. Peak consumption is a bit higher still.- Phison and Samsung based drives mostly idle at 200-250mW (Corsair Nova, Samsung 470)- Intel Marvell-based drives idle somewhere between 200 and 600mW, but numbers are hard to distill from the many flawed reviews and I haven't had one to test yet. Other Marvell-based drives usually don't support DIPM and idle higher than Intel, although this has changed since C400 (e.g. the Crucial M4).- Sandforce drives don't support DIPM, idle between 0.6W (SF-12xx) and 1W (SF-2281), also depending on capacity

Surely, if you see that the Postville Intel SSDs quote a power consumption of 75mW idle/150mW active and you are measuring 0.6W, something must be wrong?. No, they never investigate. Of course I have been an annoying user and wrote to most reviewers that made this error, but they either respond with 'nah, don't care' or 'can't change test bench, won't change reviews'. At the least, remove power consumption figures altogether if they're plainly wrong...

To be honest, that doesn't really seem like something to get too worked up over. : P

When it comes down to it, we're talking less than a watt difference in power consumption here, no matter the drive. In the real world, it's probably not going to make any noticeable difference whether your SSD is drawing 1W or 0.1W. The reviewers probably can't be bothered because it's really not that important. Maybe it will let your laptop run a few minutes longer on battery, or save a few cents in electricity over the course of a year, but in practice, it's probably a non-issue compared to the power drawn and heat dissipated by other components. It's good for the manufacturers to aim for low power consumption, but to the end-user, it's not nearly as important as things like performance, cost and reliability.

I would think that if a manufacturer were to care about the discrepancy between a reviewer's quoted power consumption figures and their own, they would let them know themselves. They're often providing the reviewers with test samples, after all, so it makes sense that they'd read the reviews and follow up on them.

Also, just as the reviewers aren't using special drivers enabling better power savings, it stands to reason that many consumers won't be either. From what I understand, DIPM is disabled by default in Windows. It also apparently decreases performance a bit, so I imagine the drive manufacturers would prefer the reviewers keep it disabled when benchmarking their drives. People will likely pay more attention to the performance figures, after all, even if the small performance difference might not be noticeable in practice. So, if most people won't be using DIPM on their drives, it makes sense to test them in that configuration, especially if the manufacturers aren't listing non-DIPM power consumption figures. They could test both modes, but then they'd also need to perform all the performance tests in both modes as well, which could make for some rather cluttered graphs.

When it comes to SSDs, reporting numbers which are completely wrong or right only in unrealistic circumstances is quite common.

Do you know any website the staff of which welcomes any corrections and is willing to work to confirm and document them?

Sure, most of them around kind of want to correct it, but in the end don't because it is a very small aspect of their testing regime for which they have to essentially completely overhaul their test suite. It then depends on their quest for science if they agree to not publish these results at all, or keep the erroneous results on the site. Many really don't care about the difference, even if it is an order off.

By the way, Cryoburner, DIPM is only off by default on Windows XP and earlier (including Server 2003). Linux support is touch and go, and most test suites are either based on Linux, or slipstreamed/automated Windows Trace benchmarks. Also, DIPM isn't the only thing that isn't properly supported in these testing environments; generally, a lot of relevant driver features simply don't work causing very different power consumption figures across the board. I've seen same-generation CPUs paired with identical GPUs that had a 'system power consumption' of over 150W in one review, and just under 50W in another. The impact of drivers and the specific power management features enabled by those drivers is just very much unknown to the average reviewer (journalist). Hell, even the impact of the power supply rating is unknown to most.

The reason I'm so adamant on SSD power consumption errors is that not a minority or majority, but simply ALL reviews are wrong. The only way to find the lowest power consumption SSD is to go by manufacturer specs, and those are often incomplete.

By default, Windows Vista enables HIPM but does not enable DIPM. The followingregistry key enables DIPM, which can help the AHCI link realize additional powersavings over HIPM. The power savings gain varies by the make and model of theSATA device attached to the link.

It's possible that may have changed in later service packs, or in Windows 7, or by certain PC manufacturers when installing Windows, but it does sound like it's disabled by default on at least some Vista systems. Information on the topic seems kind of sparse, but I see some sites detailing how to enable the feature in Windows 7, so it seems likely that at least some Windows 7 systems also have it disabled. Special drivers, like those from Intel, may enable it by default, but many people will likely stick with the default drivers.

For idle (what most PC spend their life at), Samsung seems to have a good option with PM830s, not only one of the fastest Sata III SSDs, but also very low idle consumption, SSD Test: Samsung tries again

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